My First Astro Tests - But what is this ?

[sacredblack]

Hi,

Finally found some time over the Xmas break to take out my Meade SN10 and try to photograph the Orion Nebula. I've had ok results. Next step is better polar alignment.

Anyhow while focusing the scope I came across this anomoly. Now I'm presuming it's some sort of lens flare from the intense star I've targetted but I'm sure it's not meant to be there.

Any suggestions to why this is happening ?

Steve R.

[bmitchell82]

what camera and other particulars about the scope/ conditions

[sacredblack]

Hi Brendan,

To answer your question. The camera is a Canon 1000d. It was a 10 second exposure at ISO 1600. I took the shots at around 11pm last night. Temperature was about 18 degrees and and it was a little windy.

I have a couple of other shots of similar bright stars which also contain this anomoly.

CHeers,

Steve R.

[DavidU]

What was the star in the pic?
It looks like a bright off axis star causing flaring on the corrector plate.

[sacredblack]

Hi Dave,

It's either Rigel or Canopus. I was using it for focusing (looking forward to my Moonlite Crayford replacement) and didn't really note which of the two it was.

Is this just what happens with a Schmit Newtonian when over exposing like I have ?

Steve R.

[southerncross]

Hi Steve, is the anomaly in the same spot in your other pics?

[sacredblack]

Hi Jeff,

No. It acts like a lens flare in that it will show up in opposition around a virtual centre point. Does that make sense :screwy:

Steve R.

[Visionoz]

Have you tried using a dewshield (like a lens hood for a camera lens!) to see if that will get rid of the reflection?

Cheers
Bill

[DavidU]

Probably caused by Sirus nearby.

[sacredblack]

Mmm. Yes I must try a dew shield. Don't have one as yet but if this solves the problem it's a step. I didn't mention that there was a street light that was shining just into the scope but this is a orange lamp not blue ? Also the issues doesn't appear in shots I did of the Orion Nebula. It only appears when a bright star is in the shot ?

The other thing that still bothers me is that I have about 4 shots of Altinak (orions belt) that have a similar issue. Now when I animate through those shots the anomoly rotates around a virtual centre along with Altinak ?

I'm off down the coast for a few nights and I'll take the Meade and check out the same areas and stars to see if the same issue happens. This will at least remove the street light from the equation.

Thanks again to all for some leads to dealing with this problem !

Cheers,

Steve R.